1. Which of the following is incorrect:
A. Na+
B. K–
C. Ca++
D. Cl–
E. K+
2. There is a high concentration of sodium inside of the cell. True or False.
3. There is a high concentration of potassium outside the cell. True or False.
4. The electrical potential of the resting myocytes is:
A. +70 to +90 mV
B. +100 to +120 mV
C. Approximately zero
D. –70 to –90 mV
E. –100 to –120 mV
5. The sodium-potassium ATPase pumps use ATP to push two sodium ions out and bring one potassium ion into the cell. This creates a net negative charge inside the cell. True or False.
6. Actin and myosin are the protein chains that shorten the myocytes. Which ion acts like a key that allows the troponin/tropomyosin complex to clamp these two together so they can interact?
A. Sodium
B. Potassium
C. Calcium
D. Magnesium
E. Chloride
7. The cell is polarized in the normal resting state prior to firing. True or False.
8. The cell fires when the action potential is reached. The cell is polarized during this process. True or False.
9. Which one of the following has the fastest pacemaking function:
A. SA node
B. Atrial myocytes
C. AV node
D. Bundle branches
E. Ventricular myocytes
10. The electrochemical activity of polarization–depolarization is measurable by the ECG. True or False.
11. The central nervous system primarily controls the heart and other organs through the ___________ _________ _________.
12. The autonomic nervous system is further subdivided into the ___________ nervous system and the ____________ nervous system.
13. The two subsystems are constantly in a tug-of-war over which one will control the effects of the body. In the heart, the sympathetic nervous system ______ the rate and ___________ contractility, while the parasympathetic nervous system ________ the rate and __________ contractility.
14. The primary chemical messenger for the sympathetic nervous system is ____________.
15. The primary chemical messenger for the parasympathetic nervous system is ____________.
16. ____________ is a chemical messenger that speeds conduction through the AV node.
17. ____________ is a chemical messenger that slows down conduction through the AV node.